Electric control device panel assembly with locking strip



March 2, 1965 J, F. JOHNSON ELECTRIC CONTROL DEVICE PANEL ASSEMBLY WITH LOCKING STRIP Filed Aug. 27. 62

INVENTOR. dossm F Joy/vs a/v ATTORNEY United States Patent 3,172,014 ELECTRIC CONTROL DEVICE PANEL ASSEMBLY WITH LOCKING STRIP Joseph F. Johnson, Plainville, C0nn., assignor to General Electric Company, a corporation of New York Filed Aug. 27, 1962, Ser. No. 219,698 3 Claims. (Cl. 317119) The present invention relates to electric circuit breaker panel assemblies and particularly to such panel assemblies including means for preventing the unauthorized interchanging of circuit breakers therein.

Since electric circuit breakers are protective devices which are made in different capacities and ratings and are intended to be used with branch circuits of corresponding ratings and capacities, it is important that a proper size circuit breaker be used at a particular location in a panel :and that it should not be removed and replaced by a larger size. In the interest of safety it has become desirable, and in fact required by safety regulations in various areas, to provide means whereby such circuit breakers cannot be removed from such a panel, or circuit breakers of larger capacity added. In accordance with the prior art therefore, various arrangements and schemes have been proposed for preventing or deterring the user from removing breakers or from installing ad ditional circuit breakers of particular ratings at particularly designated or predetermined positions.

A particularly effective approach to this problem is to provide means whereby the installing electrician is free to install circuit breakers of any rating at any location, but following such initial installation, an unauthorized person is prevented or deterred from removing or inserting any circuit breakers at any location within the panel. Systems of this type, which have been heretofore proposed, have however suffered from the disadvantages of being diflicult to use, or of being expensive, or both.

It is an object of the present invention to provide an electric circuit breaker panelboard in which circuit breakers can be initially installed in any desired location, but in which, after initial installation, it is not possible to remove previously installed breakers or to install addi- .tional breakers.

It is a further object of the invention to provide such an electric circuit breaker panel which does not require any substantial modification or addition to existing panels or circuit breakers;

It is a further object of the invention in one form to provide an electric circuit breaker panel which shall permit the installation or removal of previously installed breakers and the replacement or addition of further circuit breakers of a certain predetermined class but which shall at the same time prevent the removal or the addition of further circuit breakers of a second type or class.

In accordance with the invention in one form, an electric circuit breaker panelboard is provided comprising a generally planar support having a plurality of line terminal connecting means thereon generally centrally thereof, and a plurality of circuit breaker retaining means disposed along opposite edges thereof, each adapted to hold one end of a circuit breaker. Each of the circuit breakers is provided with a projecting tang portion adjacent one lower corner thereof, which extends into an aperture adjacent the aforesaid breaker retaining means. A locking strip is provided which is added to the panel base after the insertion of the desired circuit breakers and which, when in place, prevents the removal or the addition of further circuit breakers to the panel.

In accordance with the invention in one form, two types of. circuit breakers are provided, one of which can be inserted or removed even after the addition of the "ice aforesaid locking strip, and the other of which cannot be inserted or removed following such addition.

The invention will be more fully understood from the following detailed description, and its scope will be pointed out in the appended claims.

In the drawing:

FIGURE 1 is an end elevation view of a circuit breakor panel assembly incorporating the invention, one circuit controlling device being shown in partially inserted position;

FIGURE 2 is a perspective view of an electric circuit breaker as used in the panel assembly of FIGURE 1;

FIGURE 3 is a fragmentary elevation view, partially in section, of a portion of the panel assembly of FIG- URE 1;

FIGURE 4- is a view similar to FIGURE 3, the parts being shown in an intermediate position during assembly of a circuit breaker on the panel;

FIGURE 5 is a fragmentary perspective view of a pot tion of the panel of FIGURE 1;

FIGURE 6 is a fragmentary end elevation view of a panel assembly in accordance with another embodiment of the invention;

FIGURE 7 is an enlarged fragmentary elevation view of the panel assembly of FIGURE 6, portions being shown in section, and

FIGURE 8 is a view similar to FIGURE 7, showing a second type of circuit breaker mounted on a panel of FIGURE 6.

In the drawing, the invention is shown as incorporated in a panel assembly comprising a generally tray-shaped supporting pan 10 having a back wall 11 and a pair of outwardly diverging flange portions 12, a row of upstanding contact blades 13, only one shown, is disposed centrally of the supporting pan 10. The blades 13 are mounted on a suitable insulating support 14 which in turn is mounted to the back wall 11 of the pan ltl by suitable means, not shown. Connecting means, not shown, is also provided for connecting the contact blades 13 to a suitable source of electric power. A suitable mounting and connecting arrangement for the contact blades 13 and insulating support 14 is shown, for example, in prior Patent 2,897,410, Hammerly, assigned to the same assignee as the present invention.

Each of the flanges 12 carries a row of retaining hooks 15 disposed along the outer edge thereof, only one shown on each flange.

As may be best seen from FIGURE 5, each of the hooks 15 is made integral with the corresponding flange 12 by being struck out and bent from the material of the flange 12, leaving a generally rectangular opening 16 under the hook.

A plurality of circuit controlling devices or circuit breakers 17 are provided, each containing a plug-in type socket 18 mounted within one lower corner thereof as shown in FIGURE 1, which is adapted to make plug-in engagement with a corresponding contact blade 13. To permit entry of a portion of the contact blade 13 within the casing of the circuit breaker 17 in order to contact the socket 18, the casing of the circuit breaker 17 is provided with a corner slot, not shown. A circuit breaker of the type described is shown and more fully described in Patent No. 2,907,796, Fleming, assigned to the same assignee as the present invention.

Each of the circuit breakers 17 is provided with the recess 20 in the lower corner thereof opposite the socket 18, the aforesaid recess defining a mounting or retaining lug portion 21 of the casing. See FIGURE 3.

For the purpose of preventing unauthorized removal of circuit breakers, in a manner to be described, each of the circuit breakersis provided with an angularly extending locking tang 22, which is locked in place between 3 the cooperating halves 23 and 24 of the casing of the circuit breaker 17, see FIGURE 2.

As shown particularly in FIGURES 3 and 4, the locking tang 22 includes a first portion trapped between the halves of thecircuitbreaker casing and overlying a portion of the mounting lug 21, and a second portion projecting outwardly and downwardly of the circuit breaker casing.

The supporting pan also includes locking strips 12A which are attached to the respective flanges 12 by means of a screw 12B, see FIGURES; The locking strips 12A extend along the underside of the corresponding flanges 12 in such a position as to partially close the openings 16 under the retaining hooks as shown, for example, in FIGURE 3.

Assembly of circuit breakers on the panel assembly of the present invention is carried out as follows. The locking strips 12A. are removed from the flanges 12. Circuit breakers 17 of various desired ratings, are mounted in place on the panel by tilting the breaker so as to insert the locking tang in a corresponding opening 16, and to cause the corresponding hook 15 to enter the recess 2n and to overlie a portion of the locking tang 22. (The right hand breaker of FIGURE 1. as shown in such an initially positioned arrangement.) The breaker is then rotated about its engagement with the. hook 15 so as to bring the socket 18 into plug-in engagement with a portion of a corresponding contact blade 13. In this fully mounted position, the. hook 15 overlies a portion of the locking tang 22 (The left hand breaker of FIG- URE l is shown in such a fully mounted position.) When all desired circuit breakers have been mounted, the locking strips 12A are mounted in place, such as by means of special screws 1213 as shown in FIGURE 5.

When the circuit breaker is in fully mounted position,

and the locking strip 12A is also in mounted relation, the parts occupy the positions as shown in FIGURE 3. It will be seen from this figure that because of the presence of the locking strip 12A, it is not possible to rotate a circuit breaker 17 upwardly so as to remove the plug-in socket 18 from the contact blade 13. All breakers are thus securely locked in place and cannot be removed without removing the locking strips 12A. Removal of the locking strips 12A, however permits easy removal of of the circuit breaker, as shown in FIGURE 4, and ready replacement.

The screw 12B is preferably a special head type so as to render it difficult for the ordinary user or other unauthorized person to remove the locking strip 12A. Other locking devices may, of course, be utilized, including the provision of matching holes in the mounting strip and flange to permit the'insertion of a small padlock or customary wire and lead seal.

In the embodiment of the invention shown in FIG- URES' 6-8, a similar supporting pan 30 is provided having the contact blades 13 and insulating members 14 supported on the back wall 31 thereof and having out wardly directed fianges 32. Each of the flanges 32 has a series of small openings 33 therein, see FIGURES 7 and 8, disposed in a row along the outer edge of the flange 32.

The circuit breaker 17A similarly is provided with a socket, not shown, for engaging the contact blade 13 and a. recess 34 in the opposite corner. In this form of the invention, two types of circuit breakers are provided, as indicated at 17A in FIGURES 6 and 7 and 1713 in FIGURE 8. The circuit breakers 17A are as previously described but include an offset mounting tang 35 which can be inserted and removed regardless of the presence or absence of the locking strip 36. In other words, the mounting tang 35 performs a holding function for this end of such circuit breakers comparable to that performedby the hooks 15 in the first embodiment.

The circuit breakers 17B are provided with a combination mounting and locking tang 37 which is somewhat similar to the mounting tang 35, but which terminates in a return-bent tubular portion 38. The portion 38 of the tang 37 prevents removal of the circuit breaker 1713 while the locking strip 36 is in place, since it cannot pass through the restricted opening. When the locking strip 36 is removed, however, it" is possible to readily remove the circuit breakers 1713 since the portion 38' will then easily pass through the opening 33. It will be understood that while a tubular portionshas been shown, any suitable enlargement may be utilized. For instance, a partial return-bend or'hook may be used. Such a formation could not be brought through the opening 33, While the locking strip 36' is in place, since the panel enclosure would make it impossible to rotate a breaker far enough.

Since no dangerous overloading conditions can be caused by the use of the lowest rated breakers, such for example as 15 amperes breakers, such breakers are preferably constructed as shown in 17A. Circuit breakers having higher ratings, however, such for example as 20 amperes and upward, are made as shown in 1713.

While the invention has been shown and described in only two specific embodiments, it will be readily appreciated that many modifications thereof may be made, and it is therefore intended by the appended claims to cover all such modifications as fall within the true spirit and scope of the invention. For example, while the invention has been described as applied to an electric circuit breaker panelboard and electric circuit breakers, it will be readily apparent that the same may be used with other electric circuit controlling devices, such for example as switches and fuses or fuse blocks, which have mounting characteristics similar to those of the electric circuit breakers pictured.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. An electric control device panel assembly compris- (a) a support having a generally planar supporting portion,

(b) a row of apertures in said supporting portion, each of said apertures being located at acontrol device mounting location,

(0) a retaining hook adjacent each of said apertures and including a first portion extending substantially perpendicular to the plane of said supporting portion and a second portionextending substantially parallel to the said plane over said aperture,

(d) at least one control device mounted on said support and including a portion disposed and arranged to be received under said retaining hook when said control device is in said mounting location,

(e) said control device including a locking projection disposed and arranged to project through one of said apertures when said control deviceis in said mount.-

7 ing location,

( a locking strip mounted at the underside of said supporting portion by releasable mounting means and movable between a locking position and a re? leasing position, said locking strip when in said locking position including a portion disposed and arranged to obstruct movement of said projection in said aperture whereby to prevent movement of said control device in removing direction.

2. An electric control device panel assembly compris- (a) a support having a generally planar supporting portion,

(11) a plurality of aligned apertures in said support, each of said apertures being located at a control device mounting location,

(c) a plurality of aligned retaining hooks on said supporting portion, each of said retaining hooks being positioned adjacent a corresponding one of said apertures and each of said retaining hooks including a portion extending substantially perpendicular to the plane of said supporting portion and a second (5) a plurality of aligned apertures in said supporting portion extending substantially parallel to the plane portion, each of said apertures being positioned at of said supporting portion over said corresponding a corresponding control device mounting location, aperture, (c) a plurality of stationary plug-in type contacts (d) a plurality of stationary plug-in type contacts 5 carried by said support, each of said contacts being mounted on said support, each of said contacts being positioned in spaced relation with a corresponding located in spaced substantially co-planar relation one of said apertures, with a corresponding one of said retaining hooks, (d) at least one first electric circuit control device (e) at least one control device comprising a generally comprising a generally rectangular insulating casing rectangular insulating casing having a back wall and 10 having a bottom wall and opposed end walls, and opposed end walls, a mounting projection carried by said insulating cas- (f) said control device including a plug-in type elecing adjacent said bottom Wall and adjacent one of trical contact adjacent said back wall and one of said end walls, said mounting projection including a said end walls and a mounting portion adjacent said portion projecting below said bottom wall, said back wall and the other of said end walls, mounting projection having an enlarged portion adja- (g) said control device being mounted on said supcent the outer end thereof, said enlarged portion porting portion by engaging said mounting portion being adapted to pass through one of said apertures under one of said retaining hooks with said back when said circuit breaker is placed in mounted posiwall in angular relation to the plane of said supporttion on said panel, ing portion and rotating said control device about 0 (e) at least one second electric circuit control device said hook to bring said control device plug-in contact comprising a generally rectangular insulating casing into plug-in type electrical engagement with Said having a bottom wall and opposed end walls, and a stationary contact and to bring said back Wall into mounting projection carried by said insulating casing substantially parallel relation with said plane Of Said adjacent said bottom wall and adjacent one of said supporting POItISJIL end walls, said mounting projection including a pora locklng pfolectlon fixedly attached to Sald tion projecting below said bottom wall, said mountsulating casing adjacent said mounting portion and including a depending portion projecting below said bottom wall, said depending portion of said locking projection extending through one of said apertures when said circuit breaker is in mounted position,

(i) a locking strip mounted at the underside of said supporting portion by releasable mounting means, said locking strip including a portion limiting moveing projection having no enlarged portion adjacent the outer end thereof,

(f) and a locking strip removably mounted at the under side of said supporting portion and including portions overlying portions of said apertures and restricting said apertures sufficiently to prevent removal of said mounting projection of said first conment of said locking projection in said aperture, F deiicefvhile 'f g removal of aid mountwhereby to prevent reverse rocking movement of mg P J of said Second Control device when said control device to the extent necessary to dis- Said locking strip is in mountfid P nengage said control device plug-in type contact from said stationary contact, and whereby said mounting Refierences Cited y the Examiner portion of said casing and said locking projection 40 UNITED S AT S PA combine to prevent disengagement of said casing from said retaining hook while said locking strip 2530548 11/50 Stanley 317119 is in Said locking position. 2,854,501 9/ 58 Ludwig 317-99 2,916,675 12/59 Middendorf 317l19 3. An electric control device panel assembly comprising: 5

(a) a support having a generally planar supporting LARAMIE ASKIN Primary Exammer' portion, JOHN F. BURNS, Examiner. 

1. AN ELECTRIC CONTROL DEVICE PANEL ASSEMBLY COMPRISING: (A) A SUPPORT HAVING A GENERALLY PLANAR SUPPORTING PORTION, (B) A ROW OF APERTURES IN SAID SUPPORTING PORTION, EACH OF SAID APERTURES BEING LOCATED AT A CONTROL DEVICE MOUNTING LOCATION, (C) A RETAINING HOOK ADJACENT EACH OF SAID APERTURES AND INCLUDING A FIRST PORTION EXTENDING SUBSTANTIALLY PERPENDICULAR TO THE PLANE OF SAID SUPPORTING PORTION AND A SECOND PORTION EXTENDING SUBSTANTIALLY PARALLEL TO THE SAID PLANE OVER SAID APERTURE, (D) AT LEAST ONE CONTROL DEVICE MOUNTED ON SAID SUPPORT AND INCLUDING A PORTION DISPOSED AND ARRANGED TO BE RECEIVED UNDER SAID RETAINING HOOK WHEN SAID CONTROL DEVICE IS IN SAID MOUNTING LOCATION, (E) SAID CONTROL DEVICE INCLUDING A LOCKING PROJECTION DISPOSED AND ARRANGED TO PROJECT THROUGH ONE OF SAID APERTURES WHEN SAID CONTROL DEVICE IS IN SAID MOUNTING LOCATION, (F) A LOCKING STRIP MOUNTED AT THE UNDERSIDE OF SAID SUPPORTING PORTION BY RELEASABLE MOUNTING MEANS AND MOVABLE BETWEEN A LOCKING POSITION AND A RELEASING POSITION, SAID LOCKING STRIP WHEN IN SAID LOCKING POSITION INCLUDING A PORTION DISPOSED AND ARRANGED TO OBSTRUCT MOVEMENT OF SAID PROJECTION IN SAID APERTURE WHEREBY TO PREVENT MOVEMENT OF SAID CONTROL DEVICE IN REMOVING DIRECTION. 